Material Irradiation Laboratory of the Technofusion Project: Preliminary Radioprotection Assessment

The Spanish Technofusion project includes an irradiation laboratory equipped with two tandem-type accelerators (protons/deuterons and alphas) and a multi-ion cyclotron (heavy ions).

A radioprotection issue concerning activation of the irradiated samples is to establish the required "cooling" waiting period for safe handling. Samples of iron, Al₂O₃, SiO₂, and SiC are considered here.

In dealing with this task, inventory calculations have been performed using, in addition to cross-section data available in different activation libraries, experimental data for some dominant reactions that have not yet been considered in the generation of the corresponding evaluated activation cross sections. Residual dose rate results, calculated from the radioactive inventory determined using both evaluated data alone and a combination of evaluated and experimental data, are compared and the impact of the results on handling limitations analyzed.

Very affordable cooling times are found suitable for the irradiated samples. The calculated cooling times meeting safe handling requirements are expected to have high reliability for the proton beam in Al₂O₃ and the alpha beam in Fe and relatively high reliability for the proton beam in SiO₂ and Fe as well as the alpha beam in Al₂O₃ and SiO₂; only deuteron beam is satisfactory for Al₂O₃; and finally, for SiC, all cases are unsatisfactory.